Tartışma:R1
In human genetics, Haplogroup R1 is a Y-chromosome DNA haplogroup, a subgroup of haplogroup R, associated with the M173 mutation. It is dominated in practice by two very common Eurasian clades, R1a and R1b, which together are found all over Eurasia except in Southeast Asia and East Asia. However other types of R1, less well-known and un-defined so far by any identified SNP, and therefore referred to collectively simply as R1* or R-M173*, have been reported in the Americas, all over Asia and Oceania. Origins The origins of R1 remain unclear. On the one hand there is a significant presence as far south as Central Africa, for example Cameroon. Although this is generally seen as a result of back migration from Eurasia, it has been seen, especially in conjunction with high levels of R1* in Jordan, as indicative of the likelihood that R1 had origins in the Middle East. Looking at R1's relatives more generally, haplogroup R is part of the family of haplogroup P, and a sibling clade, therefore, of haplogroup Q, which is common in the Americas, and in Eurasia is associated with eastern areas such as Siberia. Such information has been used to suggest an origin for R1 to the east of the Middle East. For example, believes the evidence "suggests that southern and western Asia might be the source of this haplogroup"."Given the geographic spread and STR diversities of sister clades R1 and R2, the latter of which is restricted to India, Pakistan, Iran, and southern central Asia, it is possible that southern and western Asia were the source for R1 and R1a differentiation." Referencing Kivisild et al., felt in their review of the literature, that the case for South Asian origins is strongest, with Central Asia argued by being also worthy of consideration. Distribution Fairly common throughout Europe, South Asia and Central Asia. It also occurs in Africa, Near East and Native americans from North America. Low frecuencies in Siberia, Malay Archipelago and Indigenous Australians.Manfred Kayser et al 2002, Reduced Y-Chromosome, but Not Mitochondrial DNA, Diversity in Human Populations from West New Guinea Eurasia R1 is very common throughout all of Eurasia except East Asia and Southeast Asia. Its distribution is believed to be associated with the re-settlement of Eurasia following the last glacial maximum. Its main subgroups are R1a (M420) and R1b (M343). One subclade of haplogroup R1b (especially R1b1b2, R-M269), is the most common haplogroup in Western Europe and BashkortostanA. S. Lobov et al. (2009), "Y chromosome analysis in subpopulations of Bashkirs from Russia" (original text in Russian), while another R1a (especially R1a1a, R-M17 or R-M98) is the most common haplogroup in large parts of South Asia, Eastern Europe, Central Asia, Western China, and South Siberia.Results for R1b1 members Individuals whose Y-chromosomes possess all the mutations on internal nodes of the Y-DNA tree down to and including M207 (which defines Haplogroup R) but which display neither the M173 mutation that defines Haplogroup R1 nor the M479 mutation that defines Haplogroup R2 are categorised as belonging to group R*. Haplogroup R* has been found in 10.3% (10/97) of a sample of Burusho and 6.8% (3/44) of a sample of Kalash from northern Pakistan.Sadaf Firasat, Shagufta Khaliq, Aisha Mohyuddin, Myrto Papaioannou, Chris Tyler-Smith, Peter A Underhill and Qasim Ayub, "Y-chromosomal evidence for a limited Greek contribution to the Pathan population of Pakistan," European Journal of Human Genetics (2007) 15, 121–126. Americas In Indigenous Americans groups, R1 is the most common haplogroup after Q, specially in North America in Ojibwe people at 79%, Chipewyan 62%, Seminole 50%, Cherokee 47%, Dogrib 40% and Papago 38%.Ripan Singh Malhi et al 2008, Distribution of Y Chromosomes Among Native North Americans: A Study of Athapaskan Population History It is believed that these populations could be the result of European admixture, however the high frequency of haplogroup R1-M173 (formerly known as haplogroup P-M45b) in native northamericans also makes it unlikely that all these chromosomes result from admixture, since such a predominant European ancestry seems inconsistent with the preservation of the cultural identity of this population.Bortolini, Maria-Catira et al 2003, Y-Chromosome Evidence for Differing Ancient Demographic Histories in the Americas. (See Indigenous Amerindian genetics) Africa One isolated clade (or clades) of Y chromosomes that appear to belong to Haplogroup R1b1* (P25-derived) is found at high frequency among the native populations of northern Cameroon, such as the Kirdi, in west-central Africa, which is believed to reflect a prehistoric back-migration of an ancient proto-Eurasian population into Africa. Subclades The subclades of haplogroup R with their defining mutation, according to the stratification chart published by the 2009 International Society of Genetic Genealogy (ISOGG)http://www.isogg.org/tree/Main06.html ISOGG Website: *R **'R1' (M173/P241, M306/S1,P225, P231, P233, P234, P236, P238, P242, P245, P286, P294) ***R1* Found at low frequency in Middle East and South Asia ***'R1a (L62'/M513, L63/M511, L145/M449, L146/M420) ****R1a* ****R1a1 (SRY1532.2/SRY10831.2, L120/M516, L122/M448, M459) *****R1a1* *****R1a1a (M17, M198, M417, M512, M514, M515) Is typical in parts of Eastern Europe, Central Europe, South Asia and Central Asia. R1a1a also has a significant presence in the rest of Europe, Siberia, and the Middle East. *** 'R1b (M343)' ****R1b* ****R1b1 (P25, L278) *****R1b1* *****R1b1a (V88) ''The majority was found in northern and central Africa *****R1b1b (P297) ''Spread in Europe, Caucasus and Near East ******R1b1b1 (M73) ''Typical of Bashkortostan (Russia) and Hazaras (Pakistan) ******R1b1b2 (M269, S3, S10, S13, S17, L265) ''Typical of populations of Western Europe and Perm region, with a moderate distribution throughout Eurasia *****R1b1c (M335) R1 Haplogroup R1 contains the majority of representatives of haplogroup R in the form of its subclades, R1a and R1b. R1a The highest levels of R1a (>50%) are found across the Eurasian Steppe: West Bengal Brahmins (72%), and Uttar Pradesh Brahmins, (67%) , the Ishkashimi (68%), the Tajik population of Khojant (64%), Kyrgyz (63.5%), Sorbs (63.39%), Poles (56.4%), Ukrainians (50%) and Russians (50%)[http://www.pnas.org/content/98/18/10244.full R.Spencer Wells et al, The Eurasian Heartland: A continental perspective on Y-chromosome diversity, ''PNAS August 28, 2001, vol. 98 no. 18, pp.10244-10249.]High-Resolution Phylogenetic Analysis of Southeastern Europe Traces Major Episodes of Paternal Gene Flow Among Slavic Populations - Pericic et al. 22 (10): 1964 - Molecular Bi... .The Autochthonous Origin and a Tribal Link of Indian Brahmins: Evaluation Through Molecular Genetic Markers, by S. Sharma (1,2), E. Rai (1,2), S. Singh (1,2), P.R. Sharma (1,3), A.K. Bhat (1), K. Darvishi (1), A.J.S. Bhanwer (2), P.K. Tiwari (3), R.N.K. Bamezai (1) 1) NCAHG, SLS, JNU, New delhi; 2) Department of Human Genetics, GNDU, Amritsar; 3) Centre for Genomics, SOS zoology, JU, Gwalior, Page 273 (1344/T), Published in The American Society of Human Genetics 57th Annual Meeting, October 23–27, 2007, San Diego, California. R1a has been variously associated with: * the re-colonization of Eurasia during the Late Glacial Maximum. * the expansion of the Kurgan people from the Pontic-Caspian steppe, which is associated with the spread of the Indo-European languages. The Modern studies for R1a1 (M17) suggest that it could have originated in South Asia. It could have found its way initially from Western India (Gujarat) through Pakistan and Kashmir, then via Central Asia and Russia, before finally coming to Europe"..."as part of an archaeologically dated Paleolithic movement from east to west 30,000 years ago . R1b Haplogroup R1b probably originated in Eurasia prior to or during the last glaciation. It is the most common haplogroup in Western Europe, Bashkortostan and may have survived the LGM concentrated in refugia in southern Europe, Aegean and Bashkortostan. It is also present at lower frequencies throughout Eastern Europe, with higher diversity than in western Europe, suggesting an ancient migration of R1b from the east.Variations of R1b Ydna in Europe: Distribution and Origins R1b is also found at various frequencies in many different populations near the Ural Mountains and Central Asia, its likely region of origin. It is also found in North Africa where its frequency surpasses 10% in some parts of AlgeriaAnalysis of Y-chromosomal SNP haplogroups and STR haplotypes in an Algerian population sample. In south-eastern England the frequency of R1b is about 70%; in parts of the rest of north and western England, Spain, Portugal, Wales and Ireland, it is as high as 90%; and in parts of north-western Ireland it reaches 98%. The R1b clade appears to have a much higher degree of internal diversity than R1a, which suggests that the M343 mutation that derives R1b from R1* may have occurred considerably earlier than the SRY1532 mutation that defines R1a. Although it is rare in South Asia, some populations show relatively high percentages for R1b. These include Lambadi showing 37% , Hazara 32% and Agharia(East India) at 30% . Besides these, R1b has appeared in Balochi (8%), Chenchu (2%), Makrani (5%), Newars (10.6%), Pallan (3.5%), Pathan (10%), Indian Punjabis (7.6%) and West Bengalis (6.5%). R1b (previously called Hg1 and Eu18) is the most frequent Y-chromosome haplogroup in Europe. It is an offshoot of R1 (M173), characterised by the M343 marker.Note that in earlier literature the M269 marker, rather than M343, was used to define the R1b haplogroup. Then, for a time (from 2003 to 2005) what is now R1b1c was designated R1b3. An overwhelming majority of members of R1b are classified as R1b1 (defined by the P25 marker), the remainder as R1b*. Its frequency is highest in Western Europe (and due to modern European emigration, in parts of the Americas). The majority of R1b-carriers of European descent belong to the subclade R1b1b2 (M269). Notes References * * * * . * . * . * . * * . Also http://www.pnas.org/cgi/reprint/98/18/10244.pdf See also *Human Y-chromosome DNA haplogroup *Genealogical DNA test *Prehistoric Europe *Y-DNA haplogroups by ethnic groups *R-Arabia Y-DNA Project Category:Human Y-DNA haplogroups Category:Human evolution ru:Гаплогруппа R1 (Y-ДНК)